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Item 1.01.

Entry into a Material Definitive Agreement

As previously reported, on April 27, 2012, Watsco,
Inc., a Florida corporation (the Company), and Watsco Canada, Inc., a corporation organized under the laws of New Brunswick, Canada, and a wholly owned subsidiary of the Company, entered into an unsecured, syndicated credit
agreement with nine lenders, JPMorgan Chase Bank, N.A. as Administrative Agent, Bank of America, N.A. and Wells Fargo Bank, National Association as Co-Syndication Agents, and U.S. Bank National Association as
Documentation Agent, as amended (as amended, the Credit Facility). The Company delivered a notice under the Credit Facility, effective February 5, 2018, decreasing the borrowing capacity under the Credit Facility from
$600,000,000 to $300,000,000.

Item 2.02.

Results of Operations and Financial Condition

On February 8, 2018, the Company issued a press
release reporting its financial results for the quarter and year ended December 31, 2017. A copy of the Companys press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K and is
hereby incorporated by reference in this Item 2.02.

Item 7.01.

Regulation FD Disclosure

The information set forth in Item 2.02 of this Current Report on Form 8-K is incorporated by reference in this Item 7.01.

On February 8, 2018, the Company issued a press release
announcing a 16% increase in its annual dividend rate to $5.80 per share on each outstanding share of its Common and Class B common stock. A copy of the Companys press release is attached hereto as Exhibit 99.2 and is hereby incorporated
by reference in this Item 7.01.

The information contained in this Current Report on Form 8-K, including Exhibit
99.1 and Exhibit 99.2 attached hereto, shall be deemed furnished and not deemed filed for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that
section, nor shall it be deemed incorporated by reference in any Company filing under the Securities Act of 1933, as amended.

The record operating results reflect continued investment in technologies designed to revolutionize
Watscos customer-experience, making it easier to do business and helping customers grow their businesses more profitably. Most notably, the digitization of Watscos marketplace via e-commerce
through iOS/Android-enabled apps and websites with the industrys most in-depth database of product information made significant progress in 2017. Customer adoption increased enabling more contractors to
interact with us 24 hours a day to find products, place orders and obtain technical support. Employees are also empowered with better data, processes and capabilities to serve their customers needs.

In addition to record operating performance, Watsco generated
record operating cash flow of $302 million in 2017 on net income of $257 million.
Watsco also raised $248 million during 2017 from the sale of shares of its common stock under its previously announced at-the-market (ATM) stock
offering program, sharply reducing debt and positioning the Company to capitalize on long-term growth opportunities.

Watsco also announced today that its
Board of Directors approved a 16% increase in its annual dividend to $5.80 per share for each outstanding share of its Common and Class B common stock. The increase will be reflected in the Companys next regular dividend payment beginning
in April 2018.

Fourth Quarter Results

Key
performance metrics:



47% increase in earnings per share to a record $1.19 (includes 29 cent benefit from tax reform)



46% increase in net income to a record $43 million (includes $10 million benefit from tax reform)



6% increase in operating income to $61 million (6.4% operating margin)



Operating cash flow of $117 million



$243 million of proceeds from ATM share offering



91% reduction in debt to $22 million at December 31, 2017

Sales trends:



6% increase in sales to $964 million



7% increase in HVAC equipment (67% of sales)



4% increase in other HVAC products (29% of sales)



4% decrease in commercial refrigeration products (4% of sales)

Albert Nahmad, Watscos Chairman and
Chief Executive Officer stated: Watsco delivered another record quarter with a resumption of strong sales growth rates for residential and commercial HVAC systems from increasing unit demand and an improved mix of higher-efficiency systems.
Results also reflect further investments in technology and 150 new customer-facing employees during the course of the year to drive sales growth and market share.

1

Mr. Nahmad added: We are pleased to reward shareholders by raising our annual dividend to $5.80 per
share, reflecting our continued confidence to generate strong cash flow while investing in our business. We believe the sale of Watsco shares under the ATM program is both innovative and important as it positions the Company for almost any size
investment over the long-term and is consistent with our conservative mindset about debt.

It is important to note that the fourth quarter of each
calendar year is highly seasonal due to the nature and timing of the replacement of HVAC systems, which is strongest in the second and third quarters. Accordingly, the Companys fourth quarter financial results are disproportionately affected
by seasonality.

Full Year Results

Key performance
metrics:



13% increase in earnings per share to a record $5.81 (includes 27 cent benefit from tax reform)



14% increase in net income to a record $208 million (includes $10 million benefit from tax reform)



2% increase in operating income to a record $354 million (8.2% operating margin)



9% increase in operating cash flow to a record $302 million

Sales trends:



3% increase in sales to a record $4.34 billion



4% increase in HVAC equipment (67% of sales)



1% increase in other HVAC products (28% of sales)



Flat sales for commercial refrigeration products (5% of sales)

Cash Flow & Dividends

Operating cash flow for the full year increased 9% to a record $302 million. Since 2000, Watscos cash flow was approximately $2.2 billion
compared to net income of approximately $2.0 billion, surpassing the Companys stated goal of generating cash flow in excess of net income.

Dividends paid in 2017 increased 29% to $164 million. On February 6, 2018, Watscos Board of Directors approved a 16% increase in its annual
dividend to $5.80 per share on each outstanding share of its Common and Class B common stock. The increase will be reflected in the Companys dividend payment on April 30, 2018.

Watsco has paid dividends for over 40 consecutive years with the philosophy of sharing increasing amounts of cash flow through higher dividends while
maintaining a conservative financial position. Future increases in dividends, if any, will be considered in light of investment opportunities, cash flow, general economic conditions and the Companys overall financial condition.

Watsco raised $248 million in 2017 from the sale of 1.5 million shares of Common stock under its ATM program. The cash proceeds were used to reduce
long-term debt. As of December 31, 2017, the Companys debt-to-total capitalization was 1%.

Technology Strategy

Watsco has launched a variety of
technologies and process enhancements to transform how HVAC contractor customers are served in the marketplace. Watsco believes that speed, productivity and efficiency will be ever more critical as the digital era progresses and is investing to
ensure an unparalleled customer-experience. Since 2012, Watscos technology team has grown from approximately 60 employees to 180 employees and the present annual run-rate for technology-related spending
is approximately $23 million.

2

Watsco estimates that over 250,000 contractors and technicians visit or call one of its 560 locations each year
to get information and buy products, resulting in over 7 million sale transactions. Innovations to enhance the customer-experience include:

A.J. Nahmad, Watscos President said, We are proud of the progress weve made in regard to digitizing our
business, but weve merely scratched the surface of what is possible in terms of value creation and realization. When our customers win, we win. To that end, our culture is one of continuous improvement, which will consistently enhance our
customers businesses.

Tax Cuts and Jobs Act of 2017

Income tax expense in 2017 reflects net tax benefits of $10 million from a reduction in deferred income tax liabilities partially offset by taxes related
to undistributed earnings of our international operations and other changes. The impacts from tax reform in 2018 are being evaluated and we currently estimate our 2018 effective income tax rate (net of taxes attributable to non-controlling interest) will be in the range of 21% to 22%.

Investor Day

Watsco will host an investor and analyst meeting on Friday, March 16, 2018 in Miami, Florida from 10:00 a.m. to 1:00 p.m. by invitation
only. Leadership will provide a strategic overview of the Company, including an update of the various technology initiatives currently underway. A webcast will be provided on the Companys website at http://investors.watsco.com.

3

Conference Call Information

Date: February 8, 2018

Time: 10:00 a.m. (ET)

Webcast: http://investors.watsco.com

Dial-in number: United States (844) 883-3908 / International (412) 317-9254

A replay of the conference call will be available on the Companys website.

About Watsco

Watsco provides comfort to homes and
businesses regardless of the outdoor climate. There are approximately 92 million central air conditioning and heating systems installed in the United States that have been in service more than 10 years. Older systems often operate below
todays government mandated energy efficiency and environmental standards. Watsco has an opportunity to accelerate the replacement of these systems at a scale greater than its competitors as the movement toward reducing energy consumption and
its environmental impact continues. This is especially important since heating and cooling accounts for approximately half of the energy consumed in a typical U.S. home.

Watscos traditional sales channel is the industrys largest and currently serves 88,000 contractor businesses through 560 locations in the United
States, Canada, Mexico and Puerto Rico, and on an export basis to Latin America and the Caribbean. Watsco is a technology company, operating scalable platforms for mobile apps, e-commerce, business
intelligence and supply chain. Strategic goals are to accelerate sales and profit growth, increase the speed and convenience of serving customers and to extend its reach into new geographies and sales channels. Watsco is also developing technologies
to address the evolving buying habits of consumers in the digital economy. Over the long-term, Watsco believes its focus, scale and innovative culture offer significant advantages to address the consumer market, which is estimated to be
$88 billion annually. Additional information about Watsco may be found at http://www.watsco.com.

This document includes certain
forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements may be identified by the use of words such as will, would, anticipate,
expect, believe, plan, optimistic, goal or intend, the negative of these terms and similar references to future periods. These statements are based on managements current
expectations and are subject to uncertainty and changes in circumstances. Actual results may differ materially from these expectations due to changes in economic, business, competitive market, new housing starts and completions, capital spending in
commercial construction, consumer spending and debt levels, regulatory and other factors, including, without limitation, the effects of supplier concentration, competitive conditions within Watscos industry, seasonal nature of sales of
Watscos products, the ability of the Company to expand its business, insurance coverage risks and final GAAP adjustments. Forward-looking statements speak only as of the date the statement was made. Watsco assumes no obligation to update
forward-looking information to reflect actual results, changes in assumptions or changes in other factors affecting forward-looking information, except as required by applicable law. Detailed information about these factors and additional important
factors can be found in the documents that Watsco files with the Securities and Exchange Commission, such as Form 10-K, Form 10-Q and Form
8-K.

Weighted-average Common and Class B common shares and equivalent shares used to calculate
diluted earnings per share

33,310,064

32,662,341

32,862,633

32,616,505

Diluted earnings per share for Common and Class B common stock

$

1.19

$

0.81

$

5.81

$

5.15

5

WATSCO, INC.

Condensed Consolidated Balance Sheets

(Unaudited, in thousands)

December 31,

December 31,

2017

2016

Cash and cash equivalents

$

80,496

$

56,010

Accounts receivable, net

478,133

475,974

Inventories

761,314

685,011

Other

17,454

23,161

Total current assets

1,337,397

1,240,156

Property and equipment, net

91,198

90,502

Goodwill, intangibles, net and other

618,282

543,991

Total assets

$

2,046,877

$

1,874,649

Accounts payable and accrued expenses

$

416,233

$

314,688

Current portion of long-term obligations

244

200

Total current liabilities

416,477

314,888

Borrowings under revolving credit agreement

21,800

235,294

Deferred income taxes and other liabilities

57,623

72,719

Total liabilities

495,900

622,901

Watscos shareholders equity

1,297,953

1,005,828

Non-controlling interest

253,024

245,920

Shareholders equity

1,550,977

1,251,748

Total liabilities and shareholders equity

$

2,046,877

$

1,874,649

6

WATSCO, INC.

Condensed Consolidated Statements of Cash Flows

(Unaudited, in thousands)

Year Ended December 31,

2017

2016

Cash flow from operating activities:

Net income

$

257,290

$

235,983

Non-cash items

25,239

40,751

Changes in working capital

19,317

1,022

Net cash provided by operating activities

301,846

277,756

Cash flow from investing activities:

Investment in unconsolidated entity

(63,600

)



Capital expenditures, net

(17,708

)

(42,833

)

Net cash used in investing activities

(81,308

)

(42,833

)

Cash flow from financing activities:

Net repayments under revolving credit agreement

(213,494

)

(10,006

)

Dividends on Common and Class B Common stock

(164,147

)

(127,604

)

Distributions to non-controlling interest

(42,831

)

(38,900

)

Purchase of additional ownership from non-controlling
interest

(42,688

)

(42,909

)

Other

5,225

5,503

Proceeds from non-controlling interest for investment in
unconsolidated entity

12,720



Net proceeds from sale of Common stock

247,744



Net cash used in financing activities

(197,471

)

(213,916

)

Effect of foreign exchange rate changes on cash and cash equivalents

1,419

(226

)

Net increase in cash and cash equivalents

24,486

20,781

Cash and cash equivalents at beginning of period

56,010

35,229

Cash and cash equivalents at end of period

$

80,496

$

56,010

7

EX-99.2

Exhibit 99.2

Watsco Boosts Annual Dividend 16% to $5.80 Per Share

MIAMI, FLORIDA 
(GLOBENEWSWIRE)  February 8, 2018  Watsco, Inc. (NYSE: WSO) announced today that its Board of Directors has approved a 16% increase in its annual dividend to $5.80 per share on each outstanding share of its Common and
Class B common stock. The increase will be reflected in the Companys next regular dividend payment beginning in April 2018.

Albert H.
Nahmad, Watscos Chairman & CEO stated: We are pleased to be able to increase dividends to our shareholders and reflects our confidence in the business and is supported by our continued positive cash flow and strong balance
sheet.

Watsco has paid dividends to shareholders for more than 40 consecutive years. The Companys philosophy is to share increasing
amounts of cash flow through higher dividends while maintaining a conservative balance sheet with continued capacity to build its distribution network. Future changes in dividends are considered in light of investment opportunities, cash flow,
general economic conditions and Watscos overall financial condition.

About Watsco

Watsco provides comfort to homes and businesses regardless of the
outdoor climate. There are approximately 92 million central air conditioning and heating
systems installed in the United States that have been in service more than 10 years. Older systems often operate below todays government mandated energy efficiency and environmental standards. Watsco has an opportunity to accelerate the
replacement of these systems at a scale greater than its competitors as the movement toward reducing energy consumption and its environmental impact continues. This is especially important since heating and cooling accounts for approximately half of
the energy consumed in a typical U.S. home.

Watscos traditional sales channel is the industrys largest and currently serves 88,000 contractor
businesses through 560 locations in the United States, Canada, Mexico and Puerto Rico, and on an export basis to Latin America and the Caribbean. Watsco is a technology company, operating scalable platforms for mobile apps, e-commerce, business intelligence and supply chain. Strategic goals are to accelerate sales and profit growth, increase the speed and convenience of serving customers and to extend its reach into new geographies and
sales channels. Watsco is also developing technologies to address the evolving buying habits of consumers in the digital economy. Over the long-term, Watsco believes its focus, scale and innovative culture offer significant advantages to address the
consumer market, which is estimated to be $88 billion annually. Additional information about Watsco may be found at http://www.watsco.com.

This document includes certain
forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements may be identified by the use of words such as will, would, anticipate,
expect, believe, plan, optimistic, goal or intend, the negative of these terms and similar references to future periods. These statements are based on managements current
expectations and are subject to uncertainty and changes in circumstances. Actual results may differ materially from these expectations due to changes in economic, business, competitive market, new housing starts and completions, capital spending in
commercial construction, consumer spending and debt levels, regulatory and other factors, including, without limitation, the effects of supplier concentration, competitive conditions within Watscos industry, seasonal nature of sales of
Watscos products, the ability of the Company to expand its business, insurance coverage risks and final GAAP adjustments. Forward-looking statements speak only as of the date the statement was made. Watsco assumes no obligation to update
forward-looking information to reflect actual results, changes in assumptions or changes in other factors affecting forward-looking information, except as required by applicable law. Detailed information about these factors and additional important
factors can be found in the documents that Watsco files with the Securities and Exchange Commission, such as Form 10-K, Form 10-Q and Form
8-K.